Textile roll covering



Jan. 18, 1955 J. W. BAYMILLER TEXTILE ROLL COVERING Filed May 23, 1949 anaemic 0'" JOHN W. BAYMILLER United States Patent EX ILE RQLL CQ E HIG John W. Baymiller, Manheim Township, Lancaster C y, P as i n): to Armstrong Cork om a y, Lancaster, Pa., a Corporation of Pennsylvania Application May 21}, 1942, Serial No. 94,905

2 Claims. (01.. 19-443 This invention relates to textile roll coverings. More particularly this invention relates to rubberlike textile roll coverings possessing very high resistance to lapping up in the drafting of textile fibers.

Drawing or drafting rolls are extensively used in the textile industry for working fibrous sliver, roving, or partly finished yarns and thread in spinning and twisting machines. These drawing rolls are generally arranged in series of two or more pairs, each pair being composed of a positively driven fluted steel roll, and an idle roll having a yieldable frictional surface, which is generally positioned above and pressed against the fluted roll. The yieldable roll is provided with a suitable covering, generally referred to as a cot; and heretofore numerous materials have been proposed as a roll covering or cot. Leather has been used for a number of years; however, it suffers from several disadvantages including its cost, rapid deterioration during service, and the necessity of interruption of the spinning operation to remove lap upsfrom its circumference. Other materials which have been proposed for use as roll coverings include cork composition. These materials possess certain advantages overthe leather type cover in that their cost is initially low in comparison with leather and their service life is longer than the service life of leather cots. These cots, as in the case of leather cots, also are characterized by the tendency to lap up during the spinning operation.

Attempts have been made to employ oil-resistant synthetic rubbers to form the working surface of textile fiber drafting roll coverings. For instance, roll covers have been prepared of neoprene (polymerized chloroprene) and Perbunan, Hycar, and other similar synthetic rubbers which are butadiene acrylonitrile copolymers. These materials are also troublesome during operation in that they do not possess the requisite resistance to lapping up. Neoprene is characterized by an unusually strong tendency to lap up. The butadiene acrylonitrile type of copolymer synthetic rubber may be employed in the drafting of certain fibers wherein the tendency to lap up is less prevalent. However, cots or covers prepared from compositions containing the butadiene acrylonitrile type of synthetic rubber are unsatisfactory for use in the drafting of rayon fibers and certain cotton fibers which lap up to a considerable extent when subjected to spinning or twisting operations in equipment employing such synthetic rubber material as a roll cover.

In addition to the rubberlike and leather materials mentioned above, other synthetic rubbers as well as synthetic resins have been proposed as roll covering material. For instance, Thiokol (an organic polysulfide) has been proposed because of its extremely high oil resistance. However, this material, like neoprene, is characterized by extreme tendencies toward lapping up. Koroseal (a polyvinyl chloride synthetic rubber) is resistant to oil and forms a smooth surface cot but develops the same difiiculties as cots prepared from neoprene and Thiokol. Among the resinous materials which have been proposed are the alkyd resins. However, they do not possess the required characteristics and in operation exhibit the same tendency toward lapping up as do the synthetic rubber materials.

It is, accordingly, an object of this invention to provide a roll cover for textile units which is characterized by extreme resistance to lapping up.

It is a further object of this invention to provide a roll covering for textile drafting rolls which is characterized by resistance to lapping up and which is possessed of highly desirable surface properties during the operation of textile machinery.

Still another object of this invention is to provide a roll covering material which may be applied to the textile roll in the form of a preformed cot or sleeve.

These and other objects of this invention will become apparent to those skilled in the art upon becoming familiar with the following description when read in connection with the accompanying drawings in which:

Figure 1 is a perspective view of a roll covering in accordance with this invention;

Figure 2 is an elevational view partly in section show? ing the roll covering applied to a textile drafting roll;

Figure 3 is a vertical sectional'view of a modification of the invention in which the roll covering is applied to a suitable base material; and i i Figure 4 is a perspective view of a roll covering conraining cork granules.

I have found that the product obtained by the emulsion polymerization of a mixture containing 20% to 40% by weight of acrylonitrile, about 55% to 78% by weight of butadiene, and about 2% to 5% by weight of sorbic acid may be formed by suitable means into a textile roll covering and possesses the desired characteristics of high resistance to lapping up as well as other desirable characteristics, such as oil resistance, resistance to wear during operations, and the like.

In order to more clearly illustrate my invention, referonce may be had to the following specific example in which the polymerization product from which i make my roll coverings is prepared.

Example 1 To parts by weight of water were added 4.75 parts by Weight of Aquarex D (sodium salt of sulfate monoester of a mixture of higher fatty alcohols consisting essentially of lauryl and myristyl derivatives), 0.5 parts by weight of sodium perborate, and 5.0 parts by weight of sorbic acid. The resulting mixture was agitated well for ten minutes and showed a pH of between 3.75 and 4.0. To this material was then added a mixture containing 25.0 parts by weight of acrylonitrile, 0.35 part by weight of dodecyl mercaptan, 0.25 part by weight of Dixie Compound (diisopropyl xanthogen disulfide), and 70.0 parts by weight of butadiene-1,31. The resulting emulsion was subjected to polymerization conditions by agitating the same at a temperature of about 122 F. for eleven to thirteen hours to obtain a rubberlike polymerization product.

it is to be understood that the above method of making the rubber-like polymerization product which is employed as a textile roll covering in the practice of my invention may be varied and any of the conventional methods of making rubberlike copolymers may be followed.

The rubberlike polymerization product may be mixed with any of a number of conventional compounding agents, such as vulcanizing agents, accelerators, and the like, and vulcanized to the shape of the desired roll covering.

A typical compound for use in the manufacture of cots in accordance with my invention is illustrated in the following specific example in which all parts are given by Weight:

Example II Polymer of Example I 100.0 Clay 50.0 ZnO 5.0 TiOz 15.0 Dipolymer oil 15 .0 Sulphur 10.0 Benzo-thiazyl disulphide 2.0

The manner of forming the desired roll cover may b any of those customarily used in the manufacture of textile cots or other textile machine elements. For example, the material may be molded on a suitable mandrel in the form of a sleeve therefor, stripped from the mandrel, and cut into the desired lengths.

If desired, a laminated material may be made having the outer surface comprised of the polymerization prod- Batented Jan. 18, 1955' uct described herein. This modification of my invention is illustrated in Figure 3 in which 1 designates the wearing surface of the rubberlike polymerization product and 2 is a suitable base material such as cork-rubber compo sition.

However, generally speaking, the preferred embodiment of my invention resides in the manufacture of a covering of the cot type which may be applied to the roll as a unit.

Another embodiment of my invention includes the incorporation of cork granules in the rubberlike polymerization product. The presence of cork granules improves the eyebrow resistance of the roll covering. An eyebrow may be defined as a collection of waste fibers pulled from the roving by a cot which is not carried rearwardly of the clearer board by the rotating cot and which accumulates at the front of the clearer board in a bunchlike formation. As the eyebrow increases in size, it is occasionally pulled from the clearer board by the roving being spun and causes a hard spot in the yarn which is called a nub.

The cork granules may be included in various quantities. For instance, the amount of cork granules may advantageously be between about 25 to 125 parts by weight per 100 parts b weight of the rubberlike polymerization product. While the particle size of the cork granules may vary, generally speaking, advantageous re sults may be obtained with cork granules between about and 50 mesh. Particularly advantageous results may be obtained with cork granules falling within the range of to 30 meshes to the inch, United States Standard Sieves. The granules mav be incorporated in the rubberlike polymerization product byany suitable means.

Granules or particles ofother materials which minimize eyebrowing may be similarly employed in place of cork. Examples of such other materials are wood flour; fine mesh sand, advantageously 100 mesh; and organic filler particles, such as soft wood, balsa, and the like. Such materials may be defined as materials which minimize eyebrowing.

Roll coverings manufactured in accordance with my invention, after being subjected to commercial test still exhibited excellent surface characteristics. The roll coverings possess excellent abrasive resistance, are resistant to oils and greases, are resistant to oxidation, and do not lap up during operations. The roll coverings may be bulfed in a buffing machine without danger of melting.

It is to be understood that, although the preferred embodiment of my invention resides in roll coverings such as cots, the rubberlike polymerization product may also be employed in the manufacture of a large number of fiber-working machine elements in textile machines, such as various kinds of rolls, coverings, jackets, aprons, iarbid the like used in drafting, conveying, and working of 1 ers.

While I have illustrated and described my invention with reference to certain particular embodiments and with reference to certain specific examples, it is to be understood that the invention is not limited thereby. Therefore, changes, omissions, substitutions, and/ or additions may be made without departing from the spirit of the invention as defined in the appended claims which are intended to be limited only as required by the prior art.

I claim:

1. A textile roll covering, the working surface of which is comprised of the vulcanized emulsion polymerization product of a mixture containing about to 78% by weight of butadiene, about 20% to 40% by weight of acrylonitrile, and about 2% to 5% by weight of sorbic aci 2. A textile roll cot comprised of the vulcanized rubberlike polymerization product of a mixture containing about 55% to 78% by weight of butadiene, about 20% to 40% by weight of acrylonitrile, and about 2% to 5% by weight of sorbic acid.

References Cited in the file of this patent UNITED STATES PATENTS 2,304,656 Rockotr Dec. 8, 1942 2,422,932 Schroeder June 24, 1947 2,450,409 Baymiller Oct. 5, 1948 FOREIGN PATENTS 387,381 Great Britain Feb. 6, 1933 

